1. Field of the Invention
The invention relates to searching apparatus for providing the information to determine an exclusion keyword to specify an efficient exclusion of unwanted data when the user narrows searching object data. This is done by excluding data associated with a specified keyword. The keyword for exclusion is hereinafter referred to as an “exclusion keyword”.
2. Background Art
A searching system is employed in a computer search of an enormous amount of data accumulated in a database. If the user inputs the searching conditions, the searching system searches the data in accord with the searching conditions, and presents results to the user.
When intended data is apparent, the searching operation is not too difficult. For example, in the case where field of search is book data, it is relatively easily searched employing the book title or publisher name as the searching condition, if it is known.
However, conversely, when desired information or data is not apparent, the searching operation may be sometimes difficult. For example, to search a book, the book title or publisher name is not designated, but the contents are referenced. Also, a patent journal disclosing a similar invention to a certain invention is not designated by the application number or publication number, but searched from the viewpoint of similarity of the inventive contents. In this case, a searching keyword is specified as the searching condition, and data associated with this searching keyword is extracted from the database as the data in accord with the searching condition.
By the way, in making the searching with the searching keyword, if the searching keyword is a very common term, a great amount of data is searched. Conversely, if the searching keyword is an uncommon term, searching objects are narrowed excessively, so that a very small amount of data is searched.
In the light of the difficulty of selecting the searching keyword, it was conventionally pointed out to present the candidates for the searching keyword as described in, for example Japanese Published Unexamined Patent Application No. 11-25108 (especially pages 5 to 9, FIGS. 1 to 3).
However, the invention of Japanese Published Unexamined Patent Application No. 11-25108 simply offered the information indicating what searching keyword is employed, on the assumption that a set of searching object data is narrowed by “AND” (searching object data is narrowed into data associated with the searching keyword).
Even if the searching object data is further narrowed by referring to this information, it is understood that all of the search field is really covered with the narrowed result. For example, in searching for the similar invention, it is of course understood that all of the patent journals have been really examined. There is always a possibility that the field of search for real object of the search is excluded based on the searching using the keyword or keywords added for narrowing.
To remove such a possibility, it is effective that the set of searching object data is not narrowed by “AND” but by “NOT” (by excluding the data associated with an exclusion keyword from the set of searching object data). For example, to investigate in Japanese “batto-de boru-wo umaku miito-suru houhou” (meaning “a method for causing the bat to meet the ball”), if the searching is made using the searching keywords “batto”, “boru” and “miito”, (since Japanese word “batto” means either a bat or vat; “boru”, either a ball or bowl; and “miito”, either to meet or meat) a number of pieces of data relating with cookery are hit, whereby the cookery relevant data is excluded from the searched results by designating the exclusion keywords related with cookery.
However, the conventional methods typical of Japanese Published Unexamined Patent Application No. 11-25108 did not deal with a determination of an exclusion keyword to specify for an efficient exclusion of an unwanted piece of data.
Thus, a clear need exists to solve the above-mentioned technical problems, and especially to facilitate a user to determine an exclusion keyword to specify for an efficient exclusion of an unwanted piece of data when the user narrows searching objects.